1. Field of the Invention
The present invention relates to a mechanical input device. In particular, the present invention relates to a human machine interface for use in electronic products, which is integrated with a mechanical keypad and with touch panel functions.
2. Description of the Prior Art
With the development and progress of technologies, many electronic apparatuses have input devices, in particular mobile ones, mobile phones or PDAs for example. There are keys in these electronic apparatuses to make the users more easily input all kinds of information such as short text messages or commands, or use all kinds of functions, for example to move the cursor.
A mechanical keypad is a common input device for use in the mobile electronic apparatuses. A mechanical keypad usually includes multiple keys. Each key represents one single or multiple pre-determined signals, such as letters or symbols so that the users may choose one or more for input. Although a mechanical keypad is good at inputting certain pre-determined signals quickly, such as for chatting or for drafting documents, and is very popular for this purpose, the mechanical keypad is however too weak to input these non-pre-determined signals because each key of the mechanical keypad can only represent one or a few pre-determined signals once the mechanical keypad is used for inputting non-pre-determined signals, such as for driving a cursor in a graphic-oriented system or for constructing abstract patterns, Chinese characters for example.
Another later-introduced input device is called a “touch pad.” Compared with the mechanical keypad, there is usually no key or no raised-dot for visually impaired users in a touch pad. When being used, the touch pad detects and follows the motions of finger(s) of the users to generate corresponding results. Accordingly, the touch pad has achieved a huge success in operations based on motions such as for driving a cursor in a graphic-oriented system or for constructing abstract patterns. Nevertheless, the touch pad is less useful for inputting pre-determined signals. In addition, the know-how of conventional LCD touch pad is generally owned by foreign manufactures. On one hand, a specially designed pen is required for using the touch pad. On the other hand, the fabricating cost of the touch pad is too high but the life is too short.
In one of the published documents in the art, Japanese application 2008-270000 discloses an input device. FIG. 1 illustrates an explosive view of the prior art. The input device 1 includes multiple independent keys 7 and the element 9 is used for fixing the keys 7. The input device 1 also includes a sheet sensor 50a for sensing motions. However, the prior art does not disclose that the keycaps may be mutually connected. In addition, the prior art also lacks a backlight source as well as a light guide film (LGF) for the uniform distribution of light. As a result, this design is not good for all purposes.
Given the above, the applicants of the present invention fell the need and the inadequacy of the above-mentioned problems such as inputting pre-determined signals and performing motion operations conveniently at the same time for users in the light of the accumulated experiences in the field. The applicants of the present invention accordingly firmly believe that these problems must have room for improvement.